Floating dock for water aircraft



April 1 1930. D l,752,894

FLOATING DOCK FOR WATER AIRCRAFT Filed May 22, 1928 2 Sheets-Sheet 1 April 1, 1930. P. DEGN 2,

FLOATING DOCK FOR WATER AIRCRAFT Filed May 22, 1928 2 Sheets-Sheet 2 De" Jam/d011- 6"? r I 1 PMDe q/a. 32; Alkkfi 5r I Patented Apr. 7 1, 1930 ,UNITED STATES PATENT OEFICE PAUL DEG-N, F KIEL-DIETRICHSDORF, GERMANY, ASSIGNOR TO THE FIRM HOWALDTS- WERKE AKTIENGESELLSCHAFT, OF KIEL-NEUMUELEN DIETRIC'HSDOBF, GERMANY FLOATING DOCK. FOR WATER AIRCRAFT Application filedliay 22, 1928, Serial No. 279,827, and in Germany May 8, 1927.

V This invention relates to improvements in floating docks for water aircraft and particularly hydroplanes, flying boats and the like with laterally extending supporting surfaces or lanes.

for the purpose, for the span between the tall submersible side chambers or walls must 'be so great as not to interfere with the lifting surfaces of an aircraft to be docked.

Floating docks are known in which the side chambers are not submersible, the bottom being a submersible pontoon with columnar guide members extending vertically upwards through hollow spaces in the side chambers. Such docks also are unsuitable for water aircraft and are not practicable, for tilting of the pontoon causes jamming of the guides and such tilting must inevitably occur in practice. Moreover, the extension of the columnar guide members above the side chambers ofiers obstruction to the supporting surfaces or planes of the aircraft.

The principal obj ect'of this invention is to construct an aircraft dock in which a bottom latform is adapted to be raised and lowered I etween suitably low side chambers or walls by lifting gear. With such a dock, the lifting surfaces or planes of the aircraft are not obstructed and complete control is retained over the bottom platform in the raising and lowering thereof. i v

-Another object is to provide the bottom platform with chambers or cells adapted for stabilizing the said bottom and for reducing the dead weight to be raised by the liftin gear.

Further objects are to provide suitable dock constructions comprising side chambers conf nected by cross members and adapted for the working therein of the rising and falling bot.

ing an aircraft load away from the dock to,

' port the bottom 0 at a depth which is a little a desired place.

These and other objects and features will be described in the body of the following 4 specification with reference to examples illusrdinary floating docks are not economical I tions and in no wise limiting the invention.

Figure '5' is an end elevation of another modified construction, and

Figure 6 is an end elevation of a variant of theconstruction seen in Figures 4 and 5-.

Similar parts are designated with similar reference characters throughout the drawings. I p In Figure 1, the transverse members 6 are vertically movable with respect to the floats a, and are elevated and lowered by means of hoisting gear, the platform 0 being heavier than water and merely resting on the members b.

4 Referring to Figures-1 and '2, the dock coIn prises two side chambers a connected together at a suitable depth by transverse supports or beams b. The side chambers are hollow flotation chambers and constitute the side walls of the floating dock. As will be apparent from Figure 2, these chambers or walls do not extend to any considerable height above the surface of the water so that they do not obstruct the supporting surfaces of an aircraft seeking to enter the dock. The transverse members Z) may be of the lattice girder or openwork type illutrated. Within the dock there is a rising and falling bottom 0, the main portion of which, namely that portion upon which the aircraft will be supported,

being of the lattice or .openwork construction, if desired. In Figure 2, the bottom 0- is lowered on to the transversemembers b, and the depth of the latter is such as to suptrated, comprises horizontally disposed fluid ressure cylinders d containing plungers d fitted with cross heads 01 These cylinders are conveniently arrangedin the side chain bers at the ends thereof. Chains 0 having their ends fixed to the cross heads (Z are passed over guide sheaves e" and around compensating sheaves 0 these latter being mounted on lateral extensions f at the ends of the bottomor platform a. With'this lifting gear, itis possible to raise the bottom a by a single stroke of the plungers d from the lowered position seen in Figure 2 to the elevated position indicated by chain line in that figure, the latter position being that in which an entered aircraft is lifted clear of the water. I

a It will be apparent that other forms of hydraulic gear may be employed and that :lifting gears whether of the fluid ressure'or electrical or mechanical type may e adopted with equal facility.

In the construction illustrated in Figure 2, the .sides of the dock comprise the flotation chambers a and lower structures depending from these chambers and. adapted, if desired, for affording guidance to the bottom 0 in its rising and falling movements, these lower structures being connected together by the transverse beams or members I). In Figure 3, the last named parts are dispensed with and the sides of the dock are connected together solely by the bottom 0 itself having a suitable sliding engagement with the lower structures of such sides.

The means for guiding the bottom 0 in the structures depending from the chambers 11 during the rising and falling movement of the bottom may assume the form illustrated in Figure 2, in which guiding flanges p are rigidly mounted on the structures depending from the chambers a for engagement with the lateral extensions 7 on the bottom 0. These 3 guides serve as a convenient means for preventing movement of the bottom 0 in directions other than vertical.

In view of the inconsiderable weights to be raised in an aircraft dock, the side chamfibers may be so dimensioned that they can 56 perform slight rising and falling movements only, and since deep draught hulls are not expected to be encountered in water aircraft, the dock may be so dimensioned that even the largest aircraft may be run in, when 5 the bottom 0 is lowered, without fear of any interference between the sides of the dock and the lifting surfaces or planes of the aircraft. On account of the comparatively slight weight of aircraft to be docked, the bottom or platform 0 may in most cases be of the openwork structure referred to so that the raising and lowering of the same may be performed mechanically and more rapidly than it could be performed by pumping out 6 a hollow body. For the purpose of avoiding distorting stresses in the various arts during raising and lowering of the doc it is to be .;1'eco1'nmended that the constructional parts "beneath the chambers a, which parts serve for connecting the floating bodies together beneath the bottom a, should be connected to the floating bodies or chambers a by means of universal joints, this recommendation being particularly applicable in regard to the construction in Figures 1 and 2.

It will be noted by reference to Figure 2 of the drawings that the chambers a and the transverse members 6 are illustrated diagrammatically at s as connected by means, such as a universal joint, to permit slight relative movement of the chambers a to avoid distortion of the structure.

In the constructions described above, the

raising and lowering apparatus must balanceactually to be lifted by the gear may then. be so small that the position of equilibrlum of the bottom or platform a is just preserved and the depth of submersion of the supporting' pontoons is reduced to a minimum.

If the cells or chambers in the said bottom a are disposed so that they serve as stabilizing tanks as well as flotation chambers, the further advantage may be achieved that the platform or bottom 0 may be adapted for being run into and out of the dock for the purpose,

for example, of enabling it to. be taken, to-

gether with the aircraft lifted out of the water, to one or more workshops of the repair ard.

lar to that described with reference to the preceding figures. The bottom or platform 0 rests freely upon the transverse beams or bottom structure I). The platform a is here Referring to Figures 4 and 5, the transverse provided with three longitudinal cells or u tanks which maybe sub-divided in any suitable manner.. The two side cells or tanks 9 may remain empty permanently in which case their air contents serve for the weight-balancing above referred to as well as for stabilizing the submerged bottom or platform 0. The middle cell or tank It may be employed for balancing the weight of the platform 0. If the lateral cells or tanks 9 are employed solely as air containers, however, the middle tank It must be adapted for flooding. The filling conditions of its cells or compartments shoul preserve its condition of equilibrium during raising and lowering.

atively connected with said liftable bottom member.

4. In a floating dock for water aircraft, the combination with a liftable bottom member, of shallow floatable sides, transverse members connected with said sides for universal movement with respect thereto disposed below said bottom member, and lifting gear disposed on said sides and operatively connected with said liftable bottom member.

PAUL DEGN.

The construction illustrated in Figure 6 differs from. that illustrated in Figures 4 and 5 in respect of omission of the depending guide members 6, the sole connection between the side chambers a and the transverse and operatively connected with saidliftable means operativel members 6 supporting the platform 0 being constituted by the lifting gear e.

In constructions in accordance with this invention, it is immaterial whether the emptying of the chambers or cells is performed y pumping or by pneumatic pressure or the like, and such emptying may even be ifiperformed by draining provided that a su cient raising ofthe platform a is obtained by means of the devices 03 e. If the side tanks 9 are permanently filled with air it is only necessary to empty the middle tank It for the purpose described. The emptying of this tank is. very simple, since it may be accomplished by merely making a hose connection,

or example.

It will be understood that the invention is capable of various changes and modifications the invention herein without departin from ed in the appended claims.

described and de I claim 1. Floating dock for water aircraft comprising a liftable bottom memb'er, shallow floating sides, vertically extending guide member with sai sides, transverse members connecting sald sides below the maximum depth of submergence of said bottom member, and lifting gear disposed on said sides bottom member.

2. Floatin dock for water aircraft comprisin'g 'a li 'ble bottom'meniber, sides of connecting said bottom shallow depth and embodying flotation air chambers, a transversely extending structure suspended from and connecting between said sides and adapted for supporting said lifttransverse members said sides below said bottom member, and

able bottom member in the submerged condition of the latter, guide means operative between said bottom member and said sides, and lifting gear disposed on said sides and operatively connected with said liftable bottom me r.

'3. In a floating dock, the combination with a liftable bottom member, of floatable sides, pivotally connected with lifting gear disposed on said sides and oper- 

